WO2018225274A1 - Dispositif de direction et roue à vis sans fin - Google Patents

Dispositif de direction et roue à vis sans fin Download PDF

Info

Publication number
WO2018225274A1
WO2018225274A1 PCT/JP2017/023546 JP2017023546W WO2018225274A1 WO 2018225274 A1 WO2018225274 A1 WO 2018225274A1 JP 2017023546 W JP2017023546 W JP 2017023546W WO 2018225274 A1 WO2018225274 A1 WO 2018225274A1
Authority
WO
WIPO (PCT)
Prior art keywords
main body
worm wheel
tooth
worm gear
suppressing
Prior art date
Application number
PCT/JP2017/023546
Other languages
English (en)
Japanese (ja)
Inventor
寛之 武藤
明香 吉岡
Original Assignee
株式会社ショーワ
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社ショーワ filed Critical 株式会社ショーワ
Publication of WO2018225274A1 publication Critical patent/WO2018225274A1/fr

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H1/00—Toothed gearings for conveying rotary motion
    • F16H1/02—Toothed gearings for conveying rotary motion without gears having orbital motion
    • F16H1/04—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members
    • F16H1/12—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with non-parallel axes
    • F16H1/16—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with non-parallel axes comprising worm and worm-wheel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
    • F16H55/02—Toothed members; Worms
    • F16H55/22—Toothed members; Worms for transmissions with crossing shafts, especially worms, worm-gears

Definitions

  • the present invention relates to a steering device and a worm wheel.
  • Patent Document 1 discloses a worm gear, a worm wheel connected to the worm gear, a second bearing for rotatably supporting the worm gear, and a coil spring for biasing the second bearing in a preload direction to press the worm gear toward the worm wheel And a bearing case for supporting the second bearing and guiding the movement of the second bearing along the preload direction, and a shock absorbing member provided at a location where the second bearing moves and collides in the direction opposite to the preload direction.
  • An apparatus is disclosed.
  • the worm wheel may be formed of a resin material.
  • the worm wheel formed of the resin material may be deformed due to a temperature change.
  • the connection between the worm gear and the worm wheel becomes unstable, for example, the worm wheel is excessively pressed against the worm gear.
  • An object of the present invention is to stably connect a worm gear and a worm wheel while reducing the weight of the device.
  • the present invention for achieving the above object is provided on a worm gear which is rotated by driving a power unit, a worm wheel connected to the worm gear and rotated along with the operation of the worm gear, and provided coaxially with the worm wheel to operate the worm wheel.
  • a moving portion for moving the steered portion according to the rotation of the rotation shaft, the worm wheel is formed of a resin material, and a tooth portion is provided on the outer periphery to rotate the worm wheel
  • a suppressing portion that suppresses deformation of the main portion due to a temperature change.
  • the suppressing portion is characterized in that the linear expansion coefficient is lower than that of the main portion.
  • the tooth portion and the main body portion are characterized by being formed of the same resin material.
  • the body portion is characterized in that it comprises reinforcing fibers and the teeth portion does not contain reinforcing fibers.
  • the suppression part is characterized by being formed with the metal material.
  • it is provided with the annular member provided in the center part of a main-body part, and connecting with a rotating shaft, and the suppression part is characterized by connecting with the annular member.
  • a main body which is formed of a resin material and rotates, and a tooth shape which is formed of a resin material and which has a tooth provided on the outer periphery of the main body and connected to a worm gear.
  • a worm wheel comprising: a metal member provided outside the main body and inside the teeth.
  • the width of the metal member in the rotation axis direction is equal to or greater than the width of the main body in the rotation axis direction. Furthermore, the main body portion and the tooth profile portion are integrally formed, and the metal member is provided in the main body portion or in the tooth profile portion.
  • FIG. 2 is a cross-sectional view of the steering apparatus shown in FIG. It is sectional drawing of the assist part of this embodiment. It is a whole perspective view of the control part of this embodiment.
  • FIG. 10 is an explanatory view of a worm wheel portion of Modification 1;
  • FIG. 13 is an explanatory view of a worm wheel portion of Modification 2;
  • (A)-(D) are explanatory drawings of the worm wheel part of modification 3.
  • FIG. FIG. 18 is an explanatory view of a worm wheel portion of Modification 4;
  • FIG. 1 is an overall view of a steering device 1.
  • FIG. 2 is a cross-sectional view taken along line II-II of the steering device 1 shown in FIG.
  • the steering device 1 is a steering device for arbitrarily changing the traveling direction of the vehicle.
  • the steering device 1 of the present embodiment is an electric power steering device that assists the steering force of the driver by receiving an assisting force such as a motor.
  • the steering device 1 of the present embodiment is a so-called pinion assist type device that applies an assisting force to a pinion shaft 22 (described later) shown in FIG.
  • the axial direction of the pinion shaft 22 (described later) shown in FIG. 2 is referred to as “axial direction”.
  • the lower side of the pinion shaft 22 shown in FIG. 2 is referred to as “one side”, and the upper side of the pinion shaft 22 is referred to as “the other side”.
  • the left-right direction of the pinion shaft 22 shown in FIG. 2 is referred to as “radial direction”
  • the central axis side is referred to as “radially inner”
  • the side away from the central axis is referred to as “radially outer”.
  • the steering apparatus 1 includes an input unit 10 to which a steering force from a wheel-like steering wheel (not shown) operated by a driver is transmitted. Further, the steering device 1 receives the torque from the rack shaft 21 (an example of a moving unit) that changes the direction of the tire by connecting to a tire (an example of a steered portion), for example, And a pinion shaft 22 (an example of a rotation shaft, see FIG. 2) to be moved in a direction.
  • the steering device 1 further includes a housing 30 for accommodating various members, and an assist unit 40 for applying a steering assist force to the pinion shaft 22.
  • the input unit 10 has an input shaft 11 to which a steering force from a steering wheel operated by a driver is transmitted, and a torsion bar (not shown) attached to the inside of the input shaft 11.
  • the rack shaft 21 is a long cylindrical member. And, as shown in FIG. 2, the rack shaft 21 has a rack 21R configured by a plurality of teeth arranged in the axial direction. The rack shaft 21 is mounted such that the rack 21R meshes with a pinion 22P of the pinion shaft 22 described later. Then, the rack shaft 21 moves in the axial direction in response to the rotation of the pinion shaft 22.
  • the pinion shaft 22 is a member in which a pinion 22P is formed. Then, as described above, the pinion 22P of the pinion shaft 22 is connected to the rack 21R of the rack shaft 21. The pinion shaft 22 and the rack shaft 21 convert the rotational force of the pinion shaft 22 into movement of the rack shaft 21 in the axial direction.
  • the pinion shaft 22 receives a steering force from the input shaft 11 (see FIG. 1) via a torsion bar (not shown) and rotates. Further, in the present embodiment, the assist portion 40 is connected to the pinion shaft 22. Therefore, in addition to the steering force from the input shaft 11, the pinion shaft 22 receives the auxiliary force from the assist unit 40 and is rotatable.
  • the housing 30 has a rack housing 31R that mainly houses the rack shaft 21 and a pinion housing 31P that mainly houses the pinion shaft 22 (see FIG. 2).
  • the rack housing 31 ⁇ / b> R is a substantially cylindrical member extending in the axial direction, and is configured to be along the axial direction of the rack shaft 21.
  • the rack housing 31R holds the rack shaft 21 via a bush (not shown), and accommodates the rack shaft 21 so as to be movable in the axial direction.
  • the pinion housing 31P has a substantially cylindrical outline.
  • the pinion housing 31P is provided in the direction in which the cylindrical axial direction intersects with the axial direction of the rack housing 31R. As shown in FIG. 2, the pinion housing 31P rotatably holds the pinion shaft 22 via the other side bearing portion 35 and the one side bearing portion 36.
  • the assist unit 40 includes an electric motor 41 (an example of a power unit, see FIG. 1), a worm gear unit 50 that rotates in response to the drive of the electric motor 41, and a worm wheel unit 60 that rotates with the operation of the worm gear unit 50. Equipped with The components of the assist unit 40 will be described in detail later.
  • the steering torque applied to the steering wheel appears as a relative rotation angle between the input shaft 11 and the pinion shaft 22. Therefore, in the steering device 1, the torque detection device (not shown) grasps the steering torque based on the relative rotation angle between the input shaft 11 and the pinion shaft 22. Then, based on the output value of the torque detection device, the electronic control unit (not shown) grasps the steering torque. Furthermore, the electronic control unit controls the drive of the electric motor 41 based on the grasped steering torque.
  • the assist torque of the electric motor 41 is transmitted to the pinion shaft 22 via the worm gear unit 50 and the worm wheel unit 60.
  • the assist torque of the electric motor 41 assists the steering force of the driver applied to the steering wheel. That is, the pinion shaft 22 rotates with the steering torque generated by the rotation of the steering wheel and the auxiliary torque applied from the electric motor 41. Furthermore, the rack shaft 21 moves in the axial direction in response to the rotation of the pinion shaft 22. As a result, steering is performed by the driver's steering.
  • FIG. 3 is a cross-sectional view of the assist portion 40 of the present embodiment.
  • FIG. 4 is an overall perspective view of the suppressing portion 67 of the present embodiment.
  • the electric motor 41 rotates the output shaft 41A based on control by an electronic control unit (not shown). Then, the electric motor 41 rotates the worm gear 51.
  • the rotation direction of the electric motor 41 is both clockwise and counterclockwise.
  • a three-phase brushless motor can be used as the electric motor 41 of the present embodiment.
  • the worm gear portion 50 has a worm gear 51, a first bearing portion 52 rotatably supporting the worm gear 51, and a second bearing portion 53.
  • the worm gear 51 is a screw gear extending along the output shaft 41A of the electric motor 41. Worm gear 51 is connected to output shaft 41A.
  • the worm gear 51 rotates with the operation of the electric motor 41.
  • the first bearing portion 52 is provided on the electric motor 41 side in the axial direction of the worm gear 51.
  • the first bearing 52 rotatably supports the worm gear 51. Further, the first bearing portion 52 is fixed in position with respect to the pinion housing 31P.
  • the second bearing portion 53 is provided on the opposite side of the first bearing portion 52 in the axial direction of the worm gear 51.
  • the second bearing portion 53 rotatably supports the worm gear 51.
  • the second bearing portion 53 is fixed in position with respect to the pinion housing 31P. That is, in the present embodiment, the second bearing portion 53 fixes the worm gear 51 together with the first bearing portion 52 so as not to move in the axial direction and the radial direction.
  • the worm wheel portion 60 has a tooth shape portion 61 in which a plurality of teeth are arranged in the circumferential direction, and a main body portion 63 provided with at least the tooth shape portion 61 radially outward and rotating. Further, the worm wheel portion 60 includes a collar portion 65 (an example of an annular member) into which the pinion shaft 22 is inserted, and a suppressing portion 67 (an example of a suppressing portion, a metal member) suppressing deformation of the main body portion 63 due to temperature change.
  • a collar portion 65 an example of an annular member
  • a suppressing portion 67 an example of a suppressing portion, a metal member
  • the tooth profile portion 61 has a tooth portion 611 in which a plurality of teeth are arranged in the circumferential direction, and an annular portion 612 provided radially inward of the tooth portion 611.
  • the shape of the tooth portion 611 is not particularly limited as long as the tooth portion 611 can mesh with the tooth of the worm gear 51.
  • the annular portion 612 is only required to support the tooth portion 611, and the thickness in the radial direction is not particularly limited.
  • the toothed portion 61 is connected to the worm gear 51.
  • the tooth profile portion 61 of the present embodiment is formed of a resin material.
  • the material of the tooth shape portion 61 includes, for example, polyamide (PA) resin, polyphenylene sulfide (PPS) resin, polyether sulfone (PES) resin, polyamide imide (PAI) resin, polyether imide (PEI) resin, polyether ether Ketone (PEEK) resin, polyacetal (POM) resin, etc. can be used.
  • PA polyamide
  • PPS polyphenylene sulfide
  • PES polyether sulfone
  • PAI polyamide imide
  • PEI polyether imide
  • PEEK polyether ether Ketone
  • POM polyacetal
  • the tooth profile portion 61 is formed of a resin material, thereby achieving weight reduction and suppressing the generation of sound associated with contact with the worm gear 51.
  • the main body portion 63 faces the collar portion 65 at the inner side in the radial direction, and faces the suppression portion 67 at the outer side in the radial direction.
  • the main body portion 63 of the present embodiment is configured to be rotatable integrally with the collar portion 65 when the collar portion 65 is rotated, for example, by having a rotation stopper.
  • the main-body part 63 of this embodiment is formed by the resin material.
  • the material of the main body portion 63 includes, for example, polyamide (PA) resin, polyphenylene sulfide (PPS) resin, polyethersulfone (PES) resin, polyamide imide (PAI) resin, polyether imide (PEI) resin, polyether ether Ketone (PEEK) resin, polyacetal (POM) resin, polyethylene terephthalate (PET) resin, polypropylene (PP) resin and the like can be used.
  • PA polyamide
  • PPS polyphenylene sulfide
  • PES polyethersulfone
  • PAI polyamide imide
  • PEI polyether imide
  • PEEK polyether ether Ketone
  • POM polyacetal
  • PET polyethylene terephthalate
  • PP polypropylene
  • the main body portion 63 has an inner annular portion 631 provided radially inward and into which the collar portion 65 is inserted, and an outer annular portion 632 provided radially outward and opposed to the suppressing portion 67. Furthermore, the main body portion 63 has a disc portion 633 connected to the inner annular portion 631 and the outer annular portion 632 and a spoke portion 634 similarly connected to the inner annular portion 631 and the outer annular portion 632.
  • the inner annular portion 631, the outer annular portion 632, the disk portion 633 and the spoke portion 634 are integrally formed.
  • the inner diameter of the inner annular portion 631 is formed to be substantially the same as the outer diameter of the collar portion 65. Therefore, the collar portion 65 is press-fit into the inner annular portion 631. Thereby, the main body 63 and the collar 65 are fixed to each other. Furthermore, the axial width of the inner annular portion 631 is larger than the axial width of the outer annular portion 632 (see FIG. 2). In the present embodiment, the axial width of the inner annular portion 631 is substantially the same as the axial width of the collar portion 65.
  • the outer diameter of the outer annular portion 632 is formed to be substantially the same as the inner diameter of the suppressing portion 67. Thereby, the main body 63 and the suppressing portion 67 are fixed to each other.
  • the axial width of the outer annular portion 632 is substantially the same as the axial width of the toothed portion 61.
  • the disk portion 633 is connected to the inner annular portion 631 radially inward and to the outer annular portion 632 radially outward.
  • the spoke portion 634 is configured to include a plurality of radially extending plate-like portions 634t.
  • the plate-like portion 634 t is connected to the inner annular portion 631 radially inward and is connected to the outer annular portion 632 radially outward.
  • the plate-like portion 634t has a width in the axial direction on the radially inner side larger than a width in the axial direction on the radially outer side.
  • the spokes 634 are provided on one side and the other side of the disk 633 in the axial direction.
  • the main body portion 63 is heavy.
  • the spokes 634 by providing the spokes 634, weight reduction is achieved while maintaining a certain strength.
  • the collar portion 65 is a substantially cylindrical member. Also, the collar portion 65 is formed of a metal material. The collar portion 65 is fixed to the pinion shaft 22 by press-fitting the pinion shaft 22. In addition, since the collar part 65 is formed with a metal material as mentioned above, a linear expansion coefficient is lower than the main-body part 63 formed with a resin material. Therefore, the collar portion 65 suppresses thermal expansion deformation (deformation due to temperature change) of the main body portion 63 at the inner side in the radial direction of the main body portion 63.
  • the suppressing portion 67 is a substantially cylindrical member. And as shown in FIG. 3, the suppressing part 67 is provided in the radial direction outer side of the main-body part 63, and is provided in the radial direction inner side of the tooth part 611. As shown in FIG. That is, the suppressing portion 67 is disposed between the main body portion 63 and the tooth portion 611 in the radial direction.
  • the suppressing portion 67 may be provided at any position in the tooth shape portion 61, for example, except for the tooth portion 611. Further, the suppressing portion 67 may be provided not in the tooth profile portion 61 but in the main body portion 63. In this case, the suppression portion 67 is further provided on the outer side in the main body portion 63, so that the deformation of the main body portion 63 due to the temperature change can be further easily suppressed.
  • the suppressing portion 67 uses a material having a linear expansion coefficient lower than that of the main portion 63. Therefore, the suppressing portion 67 is less likely to be deformed due to the temperature change as compared with the main portion 63. Therefore, for example, when it is going to deform so that temperature may rise and the main-body part 63 may be thermally expanded and it may become large radially outward, the suppression part 67 will suppress the deformation
  • the material of the suppression portion 67 for example, as a metal material, a steel material (carbon steel, alloy steel, stainless steel), non-ferrous material (aluminum, magnesium, titanium or their alloys, sintering thereof) or the like is used. Can.
  • the width B ⁇ b> 1 in the axial direction of the suppressing portion 67 is set to be equal to or larger than the width B ⁇ b> 2 in the axial direction of the main body portion 63.
  • the width B1 of the suppressing portion 67 is the same as the width B2 of the main portion 63.
  • the suppressing portion 67 separates the main body portion 63 and the tooth profile portion 61 from direct contact between the main body portion 63 and the tooth profile portion 61.
  • the suppression part 67 is not limited to the above-mentioned structure.
  • the suppressing portion 67 may be provided inside the tooth shape portion 61 or inside the main body portion 63. That is, the suppressing portion 67 may not be exposed to the outer side with respect to the main body portion 63 or the tooth shape portion 61.
  • the suppressing portion 67 has an inner rotation stopping portion 671 which prevents relative rotation with the main body portion 63 at the radially inner side. Further, the suppressing portion 67 has an outer rotation stopping portion 672 which prevents relative rotation with the tooth profile portion 61 on the radially outer side.
  • the inner rotation stopping portion 671 has a plurality of grooves 671 t formed on the inner side in the radial direction of the suppressing portion 67.
  • Each groove 671t is formed extending in the axial direction.
  • a plurality of grooves 671t are provided in the circumferential direction. Further, a part of the main body portion 63 on the radially outer side is inserted into the plurality of grooves 671t. As a result, the suppressing portion 67 and the main portion 63 engage with each other, and slippage of the suppressing portion 67 and the main portion 63 in the circumferential direction (rotational direction) is prevented.
  • the depth of the groove 671t is set such that the hooking is maintained even when the main body portion 63 shrinks due to, for example, a low temperature. Then, even when the main body portion 63 contracts most, the transmission of the rotational force between the main body portion 63 and the suppressing portion 67 in the rotational direction is maintained.
  • the outer rotation stopping portion 672 has a plurality of grooves 672 t formed on the radially outer side of the suppressing portion 67.
  • Each groove 672t is formed extending in the axial direction.
  • a plurality of grooves 672t are provided in the circumferential direction. Further, a part of the tooth profile portion 61 in the radial direction is inserted into the plurality of grooves 672t. As a result, the suppressing portion 67 and the tooth profile portion 61 engage with each other, and slippage in the circumferential direction (rotational direction) of the suppressing portion 67 and the tooth profile portion 61 is prevented.
  • the manufacturing method of the worm wheel part 60 of this embodiment is demonstrated.
  • a mold corresponding to the shapes of the tooth shape portion 61 and the main body portion 63 of the present embodiment is prepared.
  • the suppressing portion 67 is installed between the shape portion forming the tooth profile portion 61 and the shape portion forming the main body portion 63.
  • a resin material for forming the tooth profile portion 61 and the main body portion 63 is filled in the mold.
  • the tooth profile portion 61 and the main body portion 63 are formed of the same resin material. Therefore, the same resin material before curing is poured into the shape portion forming the tooth shape portion 61 and the shape portion forming the main body portion 63 in the mold.
  • the main body 63, the suppressing portion 67, and the toothed portion 61 are formed.
  • the main body portion 63 may be deformed due to thermal expansion due to an increase in the outside air temperature of the steering device 1, an increase in temperature accompanying the operation, or the like. Even in this case, even if the main body portion 63 thermally expands and expands outward in the radial direction, the suppressing portion 67 suppresses the deformation of the main body portion 63 to be suppressed.
  • the main body portion 63 is deformed radially outward due to thermal expansion if the suppressing portion 67 is not provided, the tooth shape portion 61 is pushed outward in the radial direction, and as a result, the tooth shape portion 61 and the worm gear 51 It is assumed that there is excessive engagement with (see FIG. 3).
  • the suppressing portion 67 suppresses the deformation of the main body portion 63 itself.
  • the main body portion 63 is made of, for example, a resin material that is lighter than the metal material. Therefore, in the steering device 1 of the present embodiment, the weight of the device can be reduced.
  • the suppressing portion 67 may be provided in the tooth shape portion 61 in terms of suppressing the tooth portion 611 of the tooth shape portion 61 from being pushed into the worm gear 51. Further, depending on the structure of the tooth profile portion 61, for example, the annular portion 612 of the tooth profile portion 61 may not be substantially provided. And in these cases, the control part 67 should just be provided inside radial direction rather than tooth part 611 (tooth bottom). Moreover, this content is the same also in the modification mentioned later.
  • the main body portion 63 of the present embodiment may be formed of fiber reinforced plastic.
  • the main body portion 63 uses a composite material made of a synthetic resin containing reinforcing fibers such as glass fibers (GF), aramid fibers (AF), carbon fibers (CF), whiskers, polyethylene fibers (PEF), etc. .
  • GF glass fibers
  • AF aramid fibers
  • CF carbon fibers
  • PEF polyethylene fibers
  • the linear expansion coefficient of the main body portion 63 may be increased as compared to the case where the main body portion 63 is not formed of reinforced plastic, by configuring the main body portion 63 with fiber reinforced plastic.
  • the main body portion 63 contains a reinforcing fiber, while the tooth portion 611 does not contain a reinforcing fiber. Since the tooth portion 611 directly contacts the worm gear 51, there is a possibility that the reinforcing fiber peels off due to wear, and the peeled piece or the like reaches another portion. Therefore, in the present embodiment, the reinforcing fiber is contained in the main body portion 63 not in contact with the worm gear 51 to enhance the strength, and the tooth portion 611 in contact with the worm gear 51 is prevented from containing the reinforcing fiber.
  • the suppression part 67 is not interrupted in the circumferential direction, it is not limited to this aspect.
  • the suppressing portion 67 may have an intermittent portion as long as the suppressing portion 67 has a certain rigidity and the deformation of the main body portion 63 due to the thermal expansion is suppressed.
  • the suppressing portion 67 may have an overall C-shape.
  • FIG. 5 is an explanatory view of a worm wheel unit 60 of the first modification.
  • the tooth shape portion 61 and the main body portion 63 are integrally formed. That is, the tooth profile portion 61 and the main body portion 63 are not divided in the radial direction.
  • the worm wheel portion 60 has a second suppression portion 68.
  • the second suppressing portion 68 is configured to have a plurality of (two in this example) ring members 68r.
  • the ring member 68 r is provided radially outward of the main body 63 and radially inward of the teeth 611 of the tooth 61.
  • the ring member 68 r is provided on the outer annular portion 632.
  • the two ring members 68r are arranged in the axial direction.
  • a material having a linear expansion coefficient lower than that of the tooth shape portion 61 and the main body portion 63 is used for the second suppressing portion 68.
  • the second suppression portion 68 is formed of a metal material such as iron.
  • the second suppressing portion 68 suppresses the deformation of the main body portion 63 itself.
  • the worm gear 51 and the toothed portion 61 (see FIG. 3) of the worm wheel portion 60 are stably connected.
  • weight reduction can be achieved because the main body portion 63 is made of a resin material.
  • FIG. 6 is an explanatory view of a worm wheel unit 60 of the second modification.
  • illustration of the spokes 634 of the main body 63 is omitted.
  • the worm wheel unit 60 of the second modification differs from the above-described embodiment in that the third suppression unit 69 is provided.
  • the third suppressing portion 69 has the same shape as the above-described suppressing portion 67.
  • the third suppressing portion 69 is formed of a resin material having a linear expansion coefficient lower than that of the main portion 63.
  • the third suppressing portion 69 suppresses the deformation of the main body portion 63 itself.
  • the worm gear 51 see FIG. 3
  • the tooth profile portion 61 of the worm wheel portion 60 are stably connected.
  • weight reduction can be achieved because the main body portion 63 is made of a resin material.
  • the tooth-shaped portion 61 and the main portion 63 are made of the same resin material.
  • the third suppression portion 69 may be made of a composite material that is the same resin material as the tooth profile portion 61 and the main body portion 63 and that contains reinforcing fibers. In this case, the integrity of the toothed portion 61, the main body portion 63, and the third suppressing portion 69 is enhanced, and the entire worm wheel portion 60 can be strengthened.
  • FIG. 7 is an explanatory view of a worm wheel unit 60 of the third modification.
  • the worm wheel portion 60 of the third modification differs from the above-described embodiment in that the fourth suppression portion 70 is provided.
  • the fourth suppressing portion 70 is formed in a substantially disk shape.
  • the fourth suppressing portion 70 is provided radially outward of the main body portion 63 and radially inward of the tooth profile portion 61.
  • a material having a linear expansion coefficient lower than that of the tooth shape portion 61 and the main body portion 63 is used for the fourth suppressing portion 70.
  • the fourth suppression unit 70 is formed of a metal material such as iron.
  • the fourth suppressing portion 70 protrudes radially inward with an annular surface portion 71 facing in the axial direction, an outer protruding portion 72 protruding outward in the radial direction, and the like. And an inner projecting portion 73.
  • the surface portion 71 is formed as a surface facing in the axial direction, that is, a surface along the radial direction.
  • the surface portion 71 is disposed inside the main body portion 63 and radially outward of the main body portion 63.
  • the outer protrusions 72 are provided in a plurality (six in the present embodiment). Each outer projection 72 is then disposed within the annular portion 612 of the tooth 61.
  • a plurality of (in this embodiment, six) inner protrusions 73 are provided. Each inner protrusion 73 is disposed inside the main body 63 and radially inward of the surface 71.
  • the fourth suppressing portion 70 is installed in advance in the shape portion forming the main body portion 63 and the tooth shape portion 61 in the mold. Then, a resin material for forming the tooth profile portion 61 and the main body portion 63 is filled in the mold.
  • the tooth-shaped part 61, the main-body part 63, and the 4th suppression part 70 are shape
  • the fourth suppression unit 70 suppresses the deformation of the main body portion 63 itself. That is, the disk-shaped (annular) fourth suppressing portion 70 acts to restrain the main body 63 at the radially outer side of the main body 63. Further, due to the frictional force in the radial direction between the surface portion 71 and the main body portion 63, deformation in the radial direction of the main body portion 63 is suppressed. As a result, also in the third modification, the worm gear 51 and the tooth profile portion 61 of the worm wheel portion 60 are stably connected. In addition, weight reduction can be achieved because the main body portion 63 is made of a resin material. In the third modification, the frictional force of the surface portion 71 acts so as to suppress the deformation of the main body portion 63 not only when the main body portion 63 is about to be deformed by thermal expansion but also when it is being deformed due to contraction. Do.
  • outer protrusion 72 and the inner protrusion 73 enter the tooth 61 and the body 63, respectively.
  • the outer protrusion 72 and the inner protrusion 73 act as a rotation stopper with respect to the tooth 61 and the main body 63.
  • an outer recess 74 recessed inward in the radial direction at the outer peripheral portion of the surface portion 71 instead of the outer protruding portion 72 and the inner protruding portion 73;
  • An inner recess 75 may be provided at the inner peripheral portion of the surface portion 71 so as to be recessed radially outward. Parts of the tooth-shaped portion 61 and the main body portion 63 enter the outer recess 74 and the inner recess 75, respectively.
  • the outer protrusion 72 and the inner protrusion 73 act as a rotation stopper with respect to the tooth 61 and the main body 63.
  • the surface portion 71 may be provided with a plurality of grooves 76 formed along the circumferential direction.
  • the grooves 76 are provided on both the surface on one side and the surface on the other side in the axial direction of the surface portion 71. Then, when the main body portion 63 is to be deformed by thermal expansion or thermal contraction, the groove 76 increases the resistance in the radial direction. In this manner, the fourth suppression unit 70 may suppress the deformation of the main body portion 63.
  • a plurality of second grooves 77 formed in the radial direction may be provided in the surface portion 71.
  • the second groove 77 is provided on both the surface on one side and the surface on the other side in the axial direction of the surface portion 71. Then, the second groove 77 acts as a rotation stopper with respect to the tooth shape portion 61 and the main body portion 63.
  • the surface roughness is made rougher than that of the collar portion 65, a dimple formed by a plurality of irregularities, or a wall cut along the axial direction It is also possible to form a loop-like structure.
  • the configuration of the groove 76 and the second groove 77 shown in FIG. 7D may be applied to FIG. 7B and FIG. 7C.
  • FIG. 8 is an explanatory view of a worm wheel unit 60 of the fourth modification.
  • illustration of the spokes 634 of the main body 63 is omitted.
  • the worm wheel portion 60 of the fourth modification differs from the above-described embodiment in that the worm wheel portion 60 has the connection portion 80.
  • connection portion 80 is a plate-like member extending in the radial direction.
  • a plurality of (three in this example) connection portions 80 are provided.
  • each connection part 80 is connected to the collar part 65 inside radial direction.
  • each connection 80 is connected to the suppressor 67 radially outward. That is, the connection part 80 directly connects the collar part 65 and the suppression part 67.
  • the main body portion 63 is formed to include the connection portion 80 therein.
  • the fourth modification configured as described above, even if the main body portion 63 is to be deformed, the deformation of the main body portion 63 is suppressed by the suppressing portion 67, the connection portion 80, and the collar portion 65. As a result, also in the fourth modification, the worm gear 51 and the tooth profile portion 61 of the worm wheel portion 60 are stably connected. In addition, weight reduction can be achieved because the main body portion 63 is made of a resin material.
  • the color portion 65 is not an essential component except for the case where the color portion 65 is used as in the fourth modification, for example.
  • the assist unit 40 applies a steering assist force to the pinion shaft 22 to which the steering force of the driver is input.
  • the assist unit 40 in the present embodiment is not limited to being applied to this type.
  • the configuration of the assist unit 40 according to the present embodiment is, for example, applied to a mode in which a plurality of pinion shafts are connected to the rack shaft 21 and an assist force is applied to the other pinion shaft to which the steering force of the driver is not directly input. good.
  • the assist unit 40 of the present embodiment is not limited to application to a mode in which a steering assist force is applied to the pinion shaft 22.
  • the assist unit 40 according to the present embodiment may be applied to a mode in which a steering assist force is applied to a steering column connected to a steering wheel, for example.
  • SYMBOLS 1 ... steering apparatus (an example of a steering apparatus), 22 ... pinion shaft (an example of a rotating shaft), 41 ... electric motor (an example of a motive power part), 50 ... worm gear part (an example of a worm gear), 60 ... worm wheel part (worm Example of wheel 61, tooth shape (an example of tooth shape) 63, main body (an example of main body) 65 collar (an example of annular member) 67 suppression portion (suppression portion, example of metal member) ), 611 ... teeth (an example of teeth)

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Power Steering Mechanism (AREA)
  • Gear Transmission (AREA)
  • Gears, Cams (AREA)

Abstract

L'invention porte sur un dispositif de direction comprenant: une partie d'engrenage à vis sans fin 50 entraînée et entraînée en rotation par un moteur électrique 41; une partie de roue à vis sans fin 60 reliée à la partie d'engrenage à vis sans fin 50 et qui tourne conjointement avec le mouvement de la partie d'engrenage à vis sans fin 50; un arbre de pignon 22 disposé de manière coaxiale avec la partie de roue à vis sans fin 60 et qui tourne conjointement avec le mouvement de la partie de roue à vis sans fin 60; et un arbre de crémaillère 21 qui déplace une partie à diriger en réponse à la rotation de l'arbre de pignon 22. La partie de roue à vis sans fin 60 est formée à partir d'un matériau de résine, et comprend une partie de corps 63 qui tourne et présente une périphérie pourvue de dents 611, et une partie d'inhibition 67 qui inhibe la déformation due à des changements de température dans la partie de corps 63.
PCT/JP2017/023546 2017-06-09 2017-06-27 Dispositif de direction et roue à vis sans fin WO2018225274A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2017114417A JP6247419B1 (ja) 2017-06-09 2017-06-09 ステアリング装置およびウォームホイール
JP2017-114417 2017-06-09

Publications (1)

Publication Number Publication Date
WO2018225274A1 true WO2018225274A1 (fr) 2018-12-13

Family

ID=60659020

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2017/023546 WO2018225274A1 (fr) 2017-06-09 2017-06-27 Dispositif de direction et roue à vis sans fin

Country Status (2)

Country Link
JP (1) JP6247419B1 (fr)
WO (1) WO2018225274A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000329217A (ja) * 1999-05-20 2000-11-30 Nsk Ltd ウォームホイール
JP2003042264A (ja) * 2001-07-31 2003-02-13 Koyo Seiko Co Ltd 歯車、減速歯車機構及び電動式パワーステアリング装置
JP2005214338A (ja) * 2004-01-30 2005-08-11 Mitsuboshi Belting Ltd 樹脂製ウォームホイールとその製造方法
JP2007198445A (ja) * 2006-01-25 2007-08-09 Hitachi Ltd 歯車および電動パワーステアリング装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005013134A1 (de) * 2005-03-22 2006-09-28 Bayerische Motoren Werke Ag Zahnrad
DE102009000546A1 (de) * 2009-02-02 2010-08-05 Robert Bosch Gmbh Kunststoff-Spritzguss-Zahnrad, Getriebe sowie Verstellantrieb
CN103930693A (zh) * 2011-11-16 2014-07-16 本田技研工业株式会社 蜗轮蜗杆副机构

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000329217A (ja) * 1999-05-20 2000-11-30 Nsk Ltd ウォームホイール
JP2003042264A (ja) * 2001-07-31 2003-02-13 Koyo Seiko Co Ltd 歯車、減速歯車機構及び電動式パワーステアリング装置
JP2005214338A (ja) * 2004-01-30 2005-08-11 Mitsuboshi Belting Ltd 樹脂製ウォームホイールとその製造方法
JP2007198445A (ja) * 2006-01-25 2007-08-09 Hitachi Ltd 歯車および電動パワーステアリング装置

Also Published As

Publication number Publication date
JP2018203206A (ja) 2018-12-27
JP6247419B1 (ja) 2017-12-13

Similar Documents

Publication Publication Date Title
US10421479B2 (en) Reducer of electric power steering apparatus
JP4868215B2 (ja) 電動パワーステアリング装置
EP2762385B1 (fr) Dispositif d'assistance de puissance
JP4979801B2 (ja) ウォーム減速機及び電動式パワーステアリング装置
JP5719717B2 (ja) 電動リニアアクチュエータ
JP5263281B2 (ja) 電動パワーステアリング装置
EP3409976A1 (fr) Système de direction
WO2014185031A1 (fr) Palier lisse en résine synthétique
JPWO2017141965A1 (ja) ウォームホイール及びウォーム減速機
JP2007198445A (ja) 歯車および電動パワーステアリング装置
JP2006022883A (ja) ウォームホイールおよび電動パワーステアリング装置
JP2005119578A (ja) 電動パワーステアリング装置
WO2018225274A1 (fr) Dispositif de direction et roue à vis sans fin
JP2009262777A (ja) 操舵補助装置のウォーム支持構造およびそれに用いるブッシュ
JP2009074623A (ja) ボールねじ装置および電動パワーステアリング装置
JP5765628B2 (ja) 車両のステアリング装置
JP6621347B2 (ja) ギヤ装置およびステアリング装置
JP2014101071A (ja) 電動パワーステアリング装置
JP2008100642A (ja) 電動式パワーステアリング装置
JP5151154B2 (ja) ステアリング装置
JP2008126873A (ja) パワーステアリング装置
JP2016016789A (ja) 電動パワーステアリング装置
JP2008100640A (ja) 電動式パワーステアリング装置
JP2009120096A (ja) 減速装置及びそれを備えた電動パワーステアリング装置
JP2019209935A (ja) 転舵軸支持構造

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17912586

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17912586

Country of ref document: EP

Kind code of ref document: A1